The paper presents an integrated analytical, numerical and experimental study on a kind of one-dimensional finite aperiodic metastructure, with mass-in-mass unit cells optimized for the broadband wave attenuation via genetic algorithm. The study begins with the analytic wave solution of the aperiodic structure and numerically validates the correctness of the wave solution in both frequency domain and time domain. Then, the paper outlines the optimization scheme in order to connect multiple separated narrow bandgaps into a wider continuous one, including the objective function of the wave attenuation, the design variables of inner masses and their constraints. The numerical studies show the successful broadband wave attenuation with a low vibration transmissibility in one direction and two opposite directions, respectively, based on the genetic algorithm method. The maximal attenuation bandwidth of the optimized aperiodic structure increases about 90% compared with the conventional repetitive local resonance, without any mass increase. Finally, the paper gives experimental studies of a 3D-printed lattice structure with an adjustable inner mass in each cell. The measured vibrations of the fabricated structure experimentally validate the optimized aperiodic structure with the broadband wave attenuation, as well as the effectiveness of proposed optimization method.

本文对一种一维有限非周期性超结构进行了综合分析、数值和实验研究，其中质量单位单元通过遗传算法针对宽带波衰减进行了优化。研究从非周期结构的解析波解开始，数值验证了波解在频域和时域上的正确性。然后，本文概述了将多个分离的窄带隙连接成更宽的连续带隙的优化方案，包括波衰减的目标函数、内部质量的设计变量及其约束。数值研究表明，成功的宽带波衰减分别在一个方向和两个相反方向上具有低振动传递率，基于遗传算法的方法。与传统的重复局部共振相比，优化的非周期性结构的最大衰减带宽增加了约 90%，而没有任何质量增加。最后，论文给出了每个单元格内部质量可调的 3D 打印晶格结构的实验研究。装配结构的实测振动实验验证了优化的具有宽带波衰减的非周期结构，以及所提出的优化方法的有效性。该论文对 3D 打印的格子结构进行了实验研究，每个单元格的内部质量都可调节。装配结构的实测振动实验验证了优化的具有宽带波衰减的非周期结构，以及所提出的优化方法的有效性。该论文对 3D 打印的格子结构进行了实验研究，每个单元格的内部质量都可调节。装配结构的实测振动实验验证了优化的具有宽带波衰减的非周期结构，以及所提出的优化方法的有效性。